Pope Benedict XVI today praised the United Nations as being founded on the "just aspirations of the human spirit," and lent the moral support of the Catholic church to the organisation and its mission of promoting human rights.

In a 30-minute address to the UN general assembly, delivered in French and English, the pope lamented that some impoverished African and Asian nations have been excluded from "full genuine development" and only "experience the negative effects of globalisation."

The pontiff warned against scientific progress that contravenes "the created order," and said that science and technology must conform to ethical imperatives.

He said that states have a duty to protect the human rights' of their populations, and said that the international community must intervene when states are unable to guarantee that protection.

"The action of the international community and of its institutions, to the extent that it respects the principles that underlie international order, should never be seen as unjustified coercion or as being a limitation on sovereignty," he said.

He also called for a study of ways international institutions to "prevent and manage" conflict.

The 81-year old pontiff spoke on the second leg of his six-day "apostolic journey" to the US.

Also in New York, the pope will visit a synagogue, say prayers at Ground Zero and deliver a mass at Yankee stadium during his stay in the city, the first since he was elected to the papacy in 2005.

It comes the morning after the Vatican said that Benedict met privately with victims of clergy sex abuse during his trip to the United States.

The Reverend Federico Lombardi says that Benedict and Boston Cardinal Sean O'Malley met with a small group of victims and offered them encouragement and hope. Lombardi, a papal spokesman, said the Pope told victims he would pray for them, their families and all victims of clergy sex abuse.

The revelation came after the Pope also raised the child sex abuse scandal at a mass for 46,000 in the US capital city yesterday morning. "No words of mine could describe the pain and harm inflicted by such abuse," Benedict told the worshipers at the Washington Nationals baseball stadium.

The sex abuse scandal has engulfed the US Catholic church in recent years, and perhaps inevitably has become a recurring theme of the 81-year-old's first visit as pontiff to the US.

The Pope forcefully addressed the child sex abuse scandal on Wednesday, calling the affair a "deep shame". He lamented the "enormous pain" that communities have suffered from such "gravely immoral behaviour" and told his audience of US bishops that the crisis was "sometimes very badly handled". He said they must reach out with love and compassion to victims.

However, he also reminded the bishops, that the problem needs to be viewed in the wider context of secularism and the over-sexualisation of America, and called for "a determined, collective response".

At yesterday's mass the pope praised Americans as "a people of hope," but said that American Indians and blacks haven't always shared in the nation's promise. "Your ancestors came to this country with the experience of finding new freedom and opportunity," he said.

"To be sure, this promise was not experienced by all the inhabitants of this land; one thinks of the injustices endured by the native American peoples and by those brought here forcibly from Africa as slaves."

The pontiff was first introduced to the American public when he was head of the Congregation for the Doctrine of Faith and was charged with investigating paedophilia in churches worldwide. The fallout cost billions of dollars in compensation to the victims and in some cases led to dioceses filing for bankruptcy.

The pope of the time, John Paul II, was accused of failing to investigate abuse claims. During the emerging news of the scandals in December 2002, he said the allegations were part of a "planned campaign" that was "intentional, manipulated" with the aim of discrediting the church.

Around a quarter of American adults are Catholic, one of the largest Catholic populations in the world with more than 67 million followers.

But roughly a third of Americans who were raised Catholic have left the church, according to the Pew Forum on Religion and Public Life, because of Rome's stern teachings on birth control and abortion.

The church has been invigorated in recent years by immigration from Latin America, and Latinos now account for about a third of the nation's Catholics, according to the Pew forum.